Rock-drill.



PATENTED OCT. 6-, 1903.,

v w. BRADY. ROCK DRILL.

APPLI OATION'PILBD JUNE 26, 1902.

2. SHEETS-SHEET 1.

N0 MODEL.

No. 740,800. PATENTED 0cm. e, 1903.

w. BRADY.

BOOK DRILL APPLIGATI'DN rum: nnu: so, 1902.

H0 MODEL 2 SHEETS-SHEET 2.

[IQ .1": I 111111 UNITED STATES iatented October c, 19C3.

PATENT FFICE.

ROCK-DRILL.

SPECIFICATION forming part of Letters Patent No. 740,800, dated October 6, 1903- Application filed June 26, i902.

.To all whom it may concern:

Be it known that I, WILLIAM BRADY, a citizen of the United States, residing in the city and county of San Francisco, State of California, have invented an Improvement in Rock-Drills; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to improvementsin apparatus which is designed for striking blows in rapid succession, as in drilling rock or operating hammers or stamps or for any like purposes.

My invention comprises details of construe tion, which will be more fully explained by reference to the accompanying drawings, in which Figure l is a side elevation of my invention. Fig. 2 is a plan. Fig. 8 is a view illustrating. the application of the device to a stamp-ban tery. Fig. 4 is a horizontal section on the line 00 ac, Fig. 1, and also showing a modification for operating the screw of the cylinders. Fig. 5 is a side elevation of the same. Y 6 is an enlarged view of the forward end of the rock-drill. Fig. 7 is a View of the loose pinion. y

The object of this invention is to provide a power mechanism 'by which the blow upon the drill or other hammer may be struck with any degree of force and an independentlyactuating mechanism by which the drill and its actuating-pistons are returned for anew stroke,and in conjunction with this of a means foroperatinganintermediate actuating mechanism.

As shown in accompanying drawings,A and B are two cylinders connected together and in line with each other and having an intermediate space between them. These cylinders have formed upon each side guide-ribs 2.

3 is a base-piece, which is here shown in the form of a cylindrical segment and within which the cylinders lie, and the ribs 2 are slidable in grooves or channels in the upper edges of the segment 3, so that the cylinders and the drill or stamp carried by them' may be advanced with relation to this segment as the work progresses.

Beds 4 extend rearwardly and have a crosshead 5 screwed upon the rear ends. Through the center of this cross-head a screw'7, turn- $erial No. 113,233. (lilo model.)

able by a handle 6, extends into the space beneath the cylinders'and is turnable in a nut, as 8, connected with the cylinders, so that the rods 4 being "secured to the bed 3 it will be seen that by the turning of the screw the cylinders may be advanced by reason of the ribs 2 moving in the groove and the drill or other tool thus moved forward as fast as the work requires.

While this apparatus may be used, as previously stated, for striking blows for anydesired purpose, I shall hereinafter describe the tool as a drill, and the apparatus by which it is operated is equally applicable to any other form of tool.

The bed-piece 3 when used for a drill or where it is desirable to set it for striking blows in various directions is mounted upon "a supporting-bar 9 by means of a suitable adjustable clamp device, as at 10. This device may be any of the adjustable clamps employed upon power-drills.

The drill-shank 11 is fixed in the head 12 in any suitable or desired manner, and this head one. disk 1%, which is attached to it, has inclined rods 13, fixed around the periphery and passing through a ratchet-wheel 14, this ratchet-wheel being loosely turnable in the guide or casing upon the end of the cylinder B.

A pawl 15 is pressed upon by a spring 16,

so that its pointengages the teeth of ratchetwheel 14, and when the drill and the pistons and rod with which it is connected are retracted the pawl holds the ratchet 14, pre venting it from revolving. The spirally-dis posed rods 13, moving backwardly through the holes in the ratchet-wheel 14, will thus act to turn the drill to a distance depending upon the angle of the rods 13. When the drill is impelled forward by the action of the pressure medium upon the pistons within the cylinders, the ratchet-Wheel will be free to turn in an opposite direction from that 'in which the pawl holds it, and thus the drill is driven against the rock upon which it is operating in a substantially straight line, the turning of the drill taking place during the slower retraction.

17 is the piston-rod, and 18 represents the luu each of these cylinders is closed, as shown in the present illustration, so that the impelling medium which has to be used may be an explosive vapor, such as produced by gasolene or kindred substances. A stuffing-box prevents leakage at the rear of the cylinder B where the piston rod passes through. A spring 19 is located between the two cylinders, one end abutting against the rear of the cylinder B and the other end lying within the open end of the cylinder A, in such position that if the cylinders are not advanced as fast as the drill is cutting a collar or disk 20, fixed in front of the piston of the cylinder A, will strike this spring,which is su fficiently'stiff to form a cushion to check the momentum of the parts. Each cylinder is provided with an inlet and exhaust passage at its rear end, with suitable valves for the alternating admission of the explosive medium and the discharge of the spentgases after the explosion. v

These inlet-passages 21 are located upon opposite sides of their respective cylinders, as shown, and the exhaust-passages 22 are likewise located upon opposite sides of the cylinders. The inletpassages are connected through valves located as at 23, with pipes 24 connecting the valves with a gasolenetank-the source of snpplyand the forward impulse caused by the explosion in one cylinder causes the piston of the other cylinder to draw in a charge of explosive gas through its inlet valve. The return movement of this piston compresses the gas thus drawn in and the charge is ignited, causing the explosion within this cylinder and another impulse, which in turn draws in a charge of explosive vapor into the other cylinder, thus alternating the propulsion and return of the pistons and connected drill after each explosion. Means for opening the exhaust-valves of the cylinders alternately are constructed as follows:

A shaft 25 is conveniently journaled across the apparatus, as here shown. It is journaled near the front or open end and above the cylinder B. This shaft carries a pinion 26, and this pinion engages the teeth of a rackbar 27, the front end of which rack-bar is secured to the drill-carrying head 12 or to some equivalent point, so that the movement of the rack-bar is simultaneous with the movement of the drill and pistons. By means of a crank 28, fixed upon the shaft 25, the drill may be retracted by hand by reason of the engagement of the pinion 26 with the rackbar 27. It is necessary to release the parts immediately upon this retraction in order to allow the explosion to take place without acting upon the pinion' and crank-shaft, and this is efiected as follows: 29 is a collar fixed upon shaft 25, having a notch made in it, as at 30, and 31 is a pawl pressed upon by spring 32, which, together with the pawl, is carried by a collar 33, fixed to and revoluble with the shaft. When by turning the crank 28 the end of the pawl 31 engages with the notch 30 of the collar 29, the latter will be turned, and with it the pinion 26, thus retracting the rack-bar 27 and connected parts, as before described. At the instant when the retraction is complete and the pistons have reached the rear ends of their cylinders and just before the ignition of the charge within a cylinder a projecting point of the pawl 31, whichis opposite to the end engaging the notch 30, will strike a fixed pin or lug 34,

which lifts the other end of the pawl out of engagement with the notch 30, and thus leaves pinion 26 free,when the explosion with in the cylinder forces the piston and connected parts forward, the rack-bar thus acting to revolve the pinion 26 freely, because it is then disconnected from the shaft 25. As soon as the blow is struck the continued revolution of the crank 28 causes the pawl 31 to again engage the notch 30, thus connecting the pinion with the shaft, so that it can again act to retract the rack-bar 27 and connected parts.

In order to ignite the charges when compressed and to open the exhaust-valves upon the return of the pistons after the explosion, I have shown the following construction: A gear-wheel 35'is journaled so as to be engaged by a pinion 36, mounted upon the shaft 25, and a crank-pin upon the gear 35 gives motion to a rod 37, which extends rearwardly substantially parallel with the cylinders, and at its rear end this rod is connected with a crank-arm 38, fixed to the upper end of a horizontally-journaled shaft 39. This shaft carries two lever-arms and 41, projecting in opposite directions. The arm 40 acts to open the exhaust-valve of the cylinder A, and the other arm, 41, when the shaft 39 oscillates in that direction presses upon the rod 42, which is slidahle in guides and which presses against an arm, as at 43, to open the exhaust-valve of the cylinder B. The relative sizes of the pinion 36 and gear 35, which carries the crank-pin, are such that the oscillation of the shaft 39 will take place so as to alternate upon the exhaust-valves at the proper intervals. In order to actuate the igniters, which may be of suitable or well-known form, (not here shown,) these igniters have stems extending upward through the cylinder, as at 44, and each one has an arm projecting from it, as at 45. The rod 37 carries upon it the arms 46, which are designed to engage alternately with the arms 45, so as to rotate the igniter-shafts and make and break contacts, which will produce the necessary spark to explode the charge within the cylinder. The alternating motion of these igniters is effected on account of the movement of the end of the rod 37 which is connected with the crank-pin of the gear 35, while the rear end of the rod 37 is connected with the arm 38 upon the oscillat ing shaft 39. The movement of this rear end is essentially in a horizontal plane, while the movement of the opposite end is a circular movement, caused by the action of the crank.

This movement carries the contact-arms 46, which are fixed to the rod 37 alternately above and below the arms 45, carried by the ignitershafts, so that during one portion of the movement of the crank and the rod 37 one of these arms will contact with one of the igniterarms during the rearward movement of the rod 37. The other contact will be made during the forward movement of this rod 37, thus alternately actuating the igniters and cansing the explosions in their respective cylinders.

The forward feed of theapparatus may be effected by hand, or it may be produced antomatically by means of a ratchet-wheel 48, fixed upon the end of the feed-screw shaft 7 and rotated by a pawl 49, which engages it and which is carried by an arm 50, fnlcrumed as M51 and actuated by a cam or eccentric 52, which engages the other end of the arm and during its revolution which first forces the arm 50 down, and the arm is again raised.

and maintained in contact with the eccentric by a spring, as at 53. The eccentric is here shown as mountedupon a shaft 54, and this shaft is revolved by means of a sprocket 55 from another sprocket 56 upon the main shaft 25 and an intermediate sprocket-chain. The shaft 54 makes one revolution to two of the shaft 25, because the sprocket 55 is double the size of 56. If desired, a crank may be placed upon the end of the shaft 54 and power applied to turn this, and thus assist in returning the pistons after each forward impulse.

A fiy-wheel 60 is mounted upon the main shaft and serves to store up the power applied during about three-fourths of its revolution, and this power is expended during the other quarter to assist in returning the parts after a stroke.

61 is a spring, the front end of which connects with the part 12 and the rear end is'attached within the bed3. This spring is extended by the forward movement of the drill and assists in returning it and the pistons after each stroke.

Having thus described my invention, what I claim, and desiretosecure by Letters Patent, is-

1. The combination in an apparatus for striking blows of cylinders fixed axially in line and having an intermediate space, pis-' ing within the open end of the other cylin-' der, and a collar or disk on the rod in front of the piston of the last-named cylinder adapted to strike the spring said spring serving to check the momentum of the parts, substantially as described.

2'. The combination in an apparatus for striking blows, of cylinders standing axially in line, pistons and a single rod connecting the pistons, inlet and exhaust valves connecting with the rear ends of the cylinders, an oscillating shaft, lever-arms projecting from said shaft in opposite directions, one of said. arms actuating the exhaust-valve of one of the cylinders, and a rod slidable on said lastnamed cylinder and extending to the exhaustvalve of the other cylinder, said other arm of the oscillating shaft actuating said slidable rod, and means for oscillating the shaft.

3. A reciprocating apparatus consisting of cylinders in line with each other having pistons-movable in each, a piston-rod common to both, inlet and exhaust valves connected with the rear of the cylinders, a mechanism by which the pistons are moved to the rear of the cylinders to alternately compress an explosive charge, and a crank-shaft by which said mechanism is actuated, spindles upon which igniting devices are carried within the cylinders, said spindles having exterior projectin g arms, a rod having one end connected with the crank by which it is given a rotary 9 motion and the other end moving essentially in a plane, and having arms projecting from it, said arms alternately engaging the arms of the igniter-spindles during the revolution of the shaft.

4. The combination in a reciprocating apparatus of cylinders fixed in line, with pistons in each and a piston-rod common to both, an implement-carrying head fixed to the outer end of the piston-rod, inlet and exhaust valves I05 connecting with the rear ends of the cylinders, a crank-shaft and mechanism actuated thereby to'retract the pistons to the rear end of the cylinders, a pinion upon the crankshaft and a second pinion engaged thereby no having acrank-pin, a rod having one end connected with said crank-pin, and the other with the rocker-arm of an oscillating shaft, said shaft having arms adapted to alternately open the exhaust-valves of the cylinders, and other arms by which the igniters are alternately actuated whereby the charge is compressed, exploded, and exhausted alternately in each cylinder. I h Ind witness whereof I have hereunto set my W'ILLTAM BRADY.

Witnesses:

S. H. NoURsE, GEO. H. STRONG. 

